case. Dan abrams standing by to weigh in. Here's rob nelson with the evidence that police never found. Good morning, rob. Jose biaz first revealed some of what it being described as missing evidence right here on "gma" in july. But this morning, it appears that police and prosecutors are finally breaking their silence. We, the jury, find the defendant, not guilty. Reporter: This morning, abc news has learned that the sheriff's office that investigated the case admits it's missed strange internet searches made on the anthony home computer, the last day caylee was seen alive. The searches apparently were never discovered by investigators because they were using a web browser. On the day that caylee died, someone ran searches an hour after they said she first left home. Reporter: Someone searched the term "foolproof suffocation." Part of the defense was caylee drowned in the family pool. One reporter say the missed computer records an oversight. And something that baez told us overnight he doesn't believe. It's no surprise to me it was not presented in trial. Reporter: Baez now says the evidence could have helped his case because the incriminating searches were made after prosecutors contend they left the house. You have a serious problem if you're the prosecution, that is that she's home and she didn't leave at 12:50. Now baez says, had the searches been revealed into court. They would have called into question the testimony of anthony's father. Meantime, former prosecutor jeff ashton reportedly now says, quote, ashame that he didn't have the evidence. We'll talk to dan abrams about all of this. It may be a shame that the prosecutors didn't -- ashame, it's a huge piece of evidence. Casey anthony could confess and it wouldn't change anything. She could come forward and say, here's how I did it, here's why I did it, here are the details and she still couldn't be tried again because of double jeopardy basically says you cannot be tried twice for the same crime. Looking back, hypothetically, could this have changed the case? It could have, I don't think it would have. There is evidence at trial about computer searches that she did. Now, she searched allegedly for chloroform, neck breaking, other incriminating things. For those, the defense had a response, either it was her mother doing it, you can't show that it was her on the computer doing it. While this is an even bigger bombshell than any of those, i think that this jury still would have found her not guilty. There was definitely proof beyond a reasonable doubt, if you wanted to find it there, to convict casey anthony. I don't think that this particular piece of evidence would have changed this particular jury's mind. Such a high-profile case, how do you explain how the investigators missed it? You can't, particularly in a high-profile case, right, where the world is watching where you WANT TO CROSS THE "T"s AND DOT THE "Is" TO MAKE SURE YOU DO Everything right, the notion that there's a huge piece of evidence that the defense knew about was missed by law enforcement is embarrassing and shameful. And I think is going to lead to them rethinking how they do what they do. And obviously, defense under no obligation to bring it forward? Absolutely, no. The defense doesn't to give prosecutors any sort of evidence. Dan abrams, thanks very much.

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